[Nikolai] has a friend who is into fire and light shows. Her birthday was coming up, so [Nikolai] decided to build something to compliment her performances. He came up with a 10 cm LED ball (Russian, Google translation) that has a matrix of 256 LEDs wrapped around its surface.

The ball’s structural support is its own PCBs. The bottom of the ball is a simple bus – no components needed. The processor module fits into the bus along with the side arcs with LEDs on the edge. The top holds two AA batteries and a MAX1674 step up converter. The view from the inside looks like some sort of bizarre alien device. Very cool.

The central processor module is based around an ATmega88. The microprocessor controls two ‘595 for each of the 16 side panels. So far, four modes of operation have been programmed – a sine graph wrapped around a sphere, a random function, two oscillating circles, and plain old lines. The code for the LED ball is available (offsite link), and thankfully the variables are in English. An impressive piece of engineering and board layout skills.

Love them or hate them, plenty of people around the world use QR codes on a daily basis. Since he thinks they’re pretty great, Hackaday reader [falldeaf] thought it would be cool to put together an automatic QR code generator to be used on web sites.

Inspired by the custom QR logo embedding work done by our own [Brian Benchoff], his dynamic QR code generator allows you to do the same thing, but with far less work. The code requires that you have PHP and the GD library installed on your server, but other than that his code does the rest.

All you need to do is call up the page and pass along a URL, optional caption text, optional image overlay (to add your logo to the center of the code), as well as an optional hash code for tracking traffic sources. The page spits out a png image that can be used on its own, or embedded in a blog, which is what [falldeaf] plans on using it for.

If QR codes are your thing, be sure to grab a copy of his code, it will certainly be a handy tool to have around.

Onto the robot chassis, he added an Arduino to provide the brains of the bot, an Adafruit motor shield for controlling the wheels, and a Pololu Wixel for wireless communications. An iPhone is mounted on the top of the robot, which communicates with his laptop using Apple’s Facetime app. The robot is controlled from his laptop as well using the Wixel, which enables him to direct the Magician chassis as if it was attached via USB.

While he thinks the robot is pretty neat and that it works well, [Peter] already has improvements in mind. The robot chassis is a bit weak on anything but smooth surfaces, so a new set of motors and wheels are likely the first changes he’ll make. He wants to add a servo-based aiming mechanism for the phone’s camera, as well as some sensors to prevent the bot from taking a nosedive off his table.

iPhone aside, this is probably one of the cheaper mobile telepresence setups we’ve seen, so we can’t wait to hear how the improvements work out, and how much they add to the robot’s cost.

[Bertho] might have outdone himself this time. He built a Lights Out clone for the 7400 logic competition.

Lights Out is an electronic toy sold by Tiger in the mid 90s. The goal of the game is to turn a 5 by 5 grid of light up buttons off. There’s a catch, though – pressing a button toggles the state of the four surrounding buttons. Check out this Flash game that’s faithful to the original.

[Bertho] read a few Lights Out fan pages and set out to design the circuit. Most of the build is made up of shift registers: the ‘game state’ is saved in five 74hc164 shift registers and a 4557 programmable register. The board is set with a random number generator that toggles bits in the game register until a solvable puzzle is found. A truly spectacular build.

For the light-up buttons themselves, [Bertho] found an old Hack A Day post that describes putting tact switches underneath a LED. The project was put into a nice Plexiglas enclosure after 15 hours of soldering. [Bertho] was kind enough to put a video up of the game in action. Check it out after the break.